Jeweller Michael Hill International has reported an almost 9 per cent lift in sales to $425 million for the nine months ending March.

Chairman Sir Michael Hill said it the company had a positive third quarter in its key New Zealand and Australian markets, while its US stores had "traded well up" year-on-year, but sales in Canada softened.

Same-stores sales for the nine months were up 2.2 per cent to $388.4m, with like-for-like sales in New Zealand up 3.1 per cent to $85.7m and same-store sales in Australia up 2.1 per cent to $253.3m.

The NZX-listed company's professional care plan - in which customers pay for ongoing care and maintenance of their jewellery - collected revenues of $25.2m for the nine months, up 24.5 per cent year-on-year.

Of that, $8.3m was booked as actual revenue, as earnings from the plan are treated as deferred revenue and brought to income over the life of the plan.

"Cashflow remains strong and our Professional Care Plan continues to deliver good cashflow to the business and is now also contributing solidly to the group's results," Hill said.

Its shares last traded at $1.34, up 33 per cent on a year ago but below the annual high reached last month of $1.42.

In February the company reported it grew net profit for the six months to December 31 by 6 per cent year-on-year, to $27.8 million.

Revenue rose 8.3 per cent to $312.9m, while earnings before interest and tax weighed in at just under $36m - up 3.4 per cent. The retailer said a strong first quarter had been tempered by a weaker Christmas quarter with flat trading in all markets year-on-year.